There have been developments of various techniques of surface preparation methods of forming a coat or cladding layer on a surface of a metallic component by using discharge energy, involving active developments of recent discharging surface preparation methods making use of discharge energy.
Patent documents 1 and 2 have disclosed discharging surface preparation methods, including having a compact formed from powder of metal or the like, employed as an electrode, generating pulsed discharge between an end surface of the electrode and a surface of a metallic component, in a liquid or gas providing an electric insulation property. By this, they allow for using discharge energy of that, to deposit a material of the electrode or a reactant substance of the material on the surface of the metallic component, to form a coat or cladding layer.    Patent document 1: WO2006/095799    Patent document 2: WO2004/113587